JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 945 · 40 questions

Code tip (Line by line): let x = 5; makes a variable x holding 5; x = x + 2; changes it to 7. console.log(…) writes in the console; alert(…) shows a pop-up box. Text in quotes + anything = joined text: "5" + 3 → "53".

1. 1.⚡ Which JavaScript word makes a new variable? (a) for (b) alert() (c) let (d) console.log()
2. 2.⚡ Which JavaScript word runs code when true? (a) alert() (b) for (c) if (d) console.log()
3. 3.⚡ What number does this code print?
   let a = 39;
   let b = 11;
   console.log(a - b);
4. 4.⚡ Where does console.log() show its output? (a) on the printer (b) on the title bar (c) in the console (d) in the address bar
5. 5.⚡ What does this code print? (Look at the quotes!)
   let x = "2";
   let y = 4;
   console.log(x + y); (a) 6 (b) 24 (c) Error
6. 6.⚡ What does alert() show? (a) a table (b) a pop-up box (c) a picture (d) a new tab
7. 7.⚡ What does this code show?
   let name = "Zoya";
   console.log("Hi, " + name + "!"); (a) Hi, name! (b) Zoya (c) name (d) Hi, Zoya!
8. 8.⚡ What does this code show?
   let name = "Riya";
   alert("Hi, " + name + "!"); (a) name (b) Hi, Riya! (c) Riya (d) Hi, name!
9. 9.⚡ What does this code print? (Look at the quotes!)
   let x = "7";
   let y = 4;
   console.log(x + y); (a) 11 (b) 74 (c) Error
10. 10.⚡ Which JavaScript word repeats code? (a) console.log() (b) if (c) let (d) for
11. 11.⚡ What number does this code print?
    let a = 10;
    let b = 7;
    console.log(a * b);
12. 12.⚡ What number does this code print?
    let a = 22;
    let b = 9;
    console.log(a - b);
13. 13.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 6;
    console.log(x + y); (a) 12 (b) 66 (c) Error
14. 14.⚡ What number does this code print?
    let a = 8;
    let b = 2;
    console.log(a * b);
15. 15.⚡ What number does this code print?
    let a = 22;
    let b = 3;
    console.log(a + b);
16. 16.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 9;
    console.log(x + y); (a) 89 (b) 17 (c) Error
17. 17.⚡ What number does this code print?
    let marks = 19;
    marks = marks + 13;
    marks = marks - 2;
    console.log(marks);
18. 18.⚡ What does this code show?
    let name = "Meera";
    alert("Hello, " + name + "!"); (a) name (b) Hello, name! (c) Hello, Meera! (d) Meera
19. 19.⚡ Which JavaScript word shows a pop-up box? (a) alert() (b) for (c) let (d) if
20. 20.⚡ What number does this code print?
    let a = 48;
    let b = 16;
    console.log(a - b);
21. 21.⚡ What does JavaScript add to a web page? (a) only colours (b) actions and changes (c) the domain name (d) the page title
22. 22.⚡ What does this code show?
    let name = "Riya";
    console.log("Welcome, " + name + "!"); (a) Welcome, name! (b) name (c) Welcome, Riya! (d) Riya
23. 23.⚡ What number does this code print?
    let a = 54;
    let b = 2;
    console.log(a - b);
24. 24.⚡ What number does this code print?
    let a = 49;
    let b = 5;
    console.log(a - b);
25. 25.⚡ Which JavaScript word writes in the console? (a) alert() (b) console.log() (c) if (d) for
26. 26.⚡ A JavaScript file usually ends with which extension? (a) .jpg (b) .js (c) .html (d) .css
27. 27.⚡ What number does this code print?
    let a = 11;
    let b = 12;
    console.log(a * b);
28. 28.⚡ What number does this code print?
    let a = 42;
    let b = 6;
    console.log(a - b);
29. 29.⚡ What number does this code print?
    let coins = 17;
    coins = coins + 13;
    coins = coins - 9;
    console.log(coins);
30. 30.⚡ What number does this code print?
    let a = 11;
    let b = 3;
    console.log(a * b);
31. 31.⚡ What number does this code print?
    let score = 27;
    score = score + 14;
    score = score - 3;
    console.log(score);
32. 32.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 5;
    console.log(x + y); (a) Error (b) 6 (c) 15
33. 33.⚡ What number does this code print?
    let runs = 17;
    runs = runs + 20;
    runs = runs - 17;
    console.log(runs);
34. 34.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 9;
    console.log(x + y); (a) 14 (b) Error (c) 59
35. 35.⚡ What does this code show?
    let name = "Meera";
    console.log("Hi, " + name + "!"); (a) Meera (b) Hi, Meera! (c) Hi, name! (d) name
36. 36.⚡ What number does this code print?
    let a = 47;
    let b = 7;
    console.log(a - b);
37. 37.⚡ What number does this code print?
    let a = 5;
    let b = 10;
    console.log(a * b);
38. 38.⚡ What number does this code print?
    let a = 37;
    let b = 9;
    console.log(a + b);
39. 39.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 6;
    console.log(x + y); (a) Error (b) 36 (c) 9
40. 40.⚡ What number does this code print?
    let apples = 14;
    apples = apples + 11;
    apples = apples - 7;
    console.log(apples);

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